[Coco] Questions about CoCoSDC, RBSUPER, and LLCOCOSDC

[Robert Gault]

  I'm not sure if this is the right place to ask these questions but here goes.

  I have a CoCoSDC running the latest SDC-DOS (1.6 CC3) and HDB-DOS (1.4) for the CoCoSDC. I'd like 
to use as a .vhd drive the same type that is used with MESS and VCC. So far, what I have seen on the 
Internet are either the Basic partition of 256 "drives" or the OS-9 partition not both on one vhd 
for the CoCoSDC.
  Now I have been able to mount a copy of my VCC .vhd on the CoCoSDC and with a copy of the T34 and 
OS9Boot file from a CoCoSDC drive in "drive" #255 been able to auto-start HDB-DOS and from a menu 
boot NitrOS-9 just as I would with the VCC.

  What I have not been able to do is, while running NitrOS-9, access an OS-9 formatted disk in the 
Basic partition. Looking at the source code for rbsuper and llcocosdc, I can see that rbsuper uses 
bit 3 in DNS as an "HDBDOS" flag and STP as a virtual drive number when the HDBDOS flag is set.
  So with dmode /SD1 drv=0 dns=8 stp=$FF I ought to be able to read the "drive" #255 in the Basic 
partition of the .vhd drive on the CoCoSDC. It does not work.

  I can see in rbsuper.asm where the calculations are done to offset by 630 sectors per STP value 
but don't see anywhere that an offset of $5A000 is added. That might be the problem if the Basic 
partition offset is not defined anywhere for rbsuper.

  Boisy, Darren, or anyone else who has played with rbsuper, and llcocosdc, I'd love some comments. 
Should rbsuper or llcocosdc be changed? With emulators, the offsets are calculated in VEmuDsk, the 
low level driver. However, as rbsuper is doing most of the calcs, perhaps $5A000 should be defined 
and added in rbsuper.

Robert